Switchgear is defined as the apparatus used for switching electric current and apparatus. Since control and protection are two applications that are closely related to switching the switchgear refers to all such equipment that is used for switching, protecting, and controlling electricity and electrical circuits. Switchgear is composed of switches, fuses, and circuit breakers.
Switchgear MCQ
The device which detects faults in electric power systems
- Circuit breaker
- Relay
- Isolator
- Switch
Correct answer: 2. Relay
Correct statement about SF6:
- It is costly
- It has good arc quenching properties
- Has more dielectric strength
- All of these
Correct answer: 3. Has more dielectric strength
The nameplate of the circuit breaker mentions 3000 A, 5000 MVA, 132 kV. The breaking capacity of breaker is:
- 1777 A
- 3000 A
- 3687 MVA
Correct answer: 4. 5000 MVA
The rated symmetrical breaking current of a 66 kV, 3 phase oil circuit breaker rated 2000 A, 2500 MVA is:
- 15678 A
- 19354 A
- 21869 A
- 26778 A
Correct answer: 3. 21869 A
A current of 200 A is flowing through line. All in sudden it rises by 50 A. Which of the following is expected:
- Open circuit fault
- Short circuit fault
- Line to ground fault
- Overloading
Correct answer: 4. Overloading